Table 1.

Definition of the squaring errors for all six geometrical configurations of the task

Plane	Adjustable dimension	Reference dimension	Task error
Frontal	LA	LO	${\epsilon }_{LA-LO}=l_{LA}-l_{LO}$
	LO	LA	${\epsilon }_{LO-LA}=l_{LO}-l_{LA}$
Transversal	LA	AP	${\epsilon }_{LA-AP}=l_{LA}-l_{AP}$
	AP	LA	${\epsilon }_{AP-LA}=l_{AP}-l_{LA}$
Sagittal	LO	AP	${\epsilon }_{LO-AP}=l_{LO}-l_{AP}$
	AP	LO	${\epsilon }_{AP-LO}=l_{AP}-l_{LO}$